Seed planters often include several seed planting units transversely arranged relative to a travel direction of the seed planter. Each seed planting unit may include a seed tube for depositing seeds into seed furrows during seed planting. The seed planting unit may also include a furrow device, such as a seed follower for controlling the positions of the seed as they are released from the seed tube. The seed follower may be positioned in an aft position relative to the seed tube and may be attached to the seed tube. The seed unit may be further equipped with a seed sensor assembly for detecting the passage of seeds for accurate planting.